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Background

In 1981, Lamport(Lamport 1981) proposed a password-based authentication scheme, where the server stores passwords. This scheme is vulnerable to passive attacks, as once the password table is leaked or compromised, the intruder can modify the passwords stored in the system. Later, Hwang et al. (Hwang, Chen, and Laih 1990) proposed an improved protocol that overcame the weaknesses of Lamport’s scheme. Subsequently, Yang and Shieh (Yang and Shieh 1999) introduced two password authentication schemes using smart cards based on timestamps and nonces.

Code

  #| code-fold: show
  #| code-summary: "Show the code"
  import matplotlib.pyplot as plt
  import numpy as np

  # Generate some data
  x = np.linspace(0, 10, 100)
  y = np.cos(x)

  # Create a plot
  plt.figure(figsize=(10, 6))
  plt.plot(x, y, label='Cosine Wave')
  plt.title('Any Plot')
  plt.xlabel('X')
  plt.ylabel('Y')
  plt.legend()
  plt.grid(True)

  plt.show(）

Plot